Foil bag stacks, and method and device for producing such bags

ABSTRACT

Foil bags are formed as new paper bags by fusing together two webs and tying a detachable strap which has a suspension opening to one said opening of each bag, the strap being separated by a perforation line from the respective side of the bag. A pocket is formed at the end of the bag opposite the insertion opening and can have a flap provided with an adhesive strip covered by a masking layer.

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application is related to provisional application 60/212,025filed Jun. 16, 2000.

FIELD OF THE INVENTION

[0002] The invention relates first to a stack of interconnected,elongated bags of plastic foil or film, particularly newspaper bags,with preferably at least one additional pocket and with a suspensionelement in the area of the insertion opening of the bag, which has atleast one suspension opening and which is detachably connected withother bags in the stack.

[0003] The invention also relates to the manufacture of such bags andparticularly to a method and apparatus for making such bags and pads ofsuch bags.

BACKGROUND OF THE INVENTION

[0004] Bags of the mentioned kind are used especially for the extensiveprotection of newspapers, magazines or the like against weatherinfluences. Frequently these elongated bags have an additional pocket,into which a diskette or the like can be introduced.

[0005] As a rule, the bags are assembled in stacks or pads of 10 to 20pieces, and up to a maximum of 25 pieces and are held together by a griphandle made of cardboard. This grip handle, serving as a suspensionelement, is fastened with staples or clips to the margin of a tear-offstrap.

[0006] In practice such a stack is carried along by a delivery person,who first fills the bag with a magazine or newspaper, if this was notpreviously done, and then tears the filled bag off the stack, in orderto deliver it to a place accessible to the recipient.

[0007] The use of three different materials, namely cardboard for thegrip handle, iron for the staples or clips and plastic material for theactual bag results in considerable recycling expenses, since thementioned materials have to be collected separately from each other.Besides the production of such bags is quite complicated, so that inpractice such bags can be produced only at a cycling speed ofapproximately 40 to 60 per minute.

OBJECTS OF THE INVENTION

[0008] It is the object of the invention to provide a stack of severalinterconnected elongated bags of plastic foil, particularly newspaperbags, which can be easily transported and handled.

[0009] It is also an object to provide a method for the production ofsuch bags which can be interconnected in stacks and which makes possiblesimple and cost-effective production.

[0010] A further object is to provide a device which uses widely knownelements and allows the production of the mentioned bags withcomparatively high cycling speeds.

SUMMARY OF THE INVENTION

[0011] These objects are achieved in accordance with the invention inthat the suspension element is formed by a unilaterally projectingtear-off segment of plastic foil. This tear-off segment can for instancebe formed by a separate strip fused with the one bag wall in the area ofthe insertion opening, basically parallel to a perforation line. Thisinsertion opening can be advantageously closed by means of a drawstringor a rainprotection flap.

[0012] On the side of the bag opposite to the insertion opening a pocketcan be attached and the pocket can have a unilaterally projecting flapat its filling opening which is basically parallel with the insertionopening. The flap can optionally be made in one piece from the pocketmaterial and provided on its inside with an adhesive strip which can becovered with a protective or masking strip.

[0013] The connection means for interconnecting the individual bags inthe stack can be formed as a interlocking device and, in addition, astrap unwinding mechanism can be provided. Because of the continuousfeeding of a strap strip a comparatively high cycling speed can beachieved, for instance of 100 to 125 cycles/minute.

[0014] The device can have two fusion separation tools arrangedsubstantially transversely with respect to the direction of the advancemotion of the plastic foil or film webs, which move synchronously up anddown. The collection mechanism arranged downstream in the direction ofthe advance motion of the plastic foil webs can have pin-type stackingbelts of a pin-type stacker, wherein the bags with the strap strips aretaken up by the stacker belts, whereby, until they reach the stackerbelts, the bags are held by the pins of the transport belts and areknocked off by a take-down device in the area of the pin-type stackingconveyor, and afterwards are interlocked in the area of the strap.

[0015] More particularly, the bag stack can comprise:

[0016] a plurality of elongated plastic foil bags each having a pair ofopposite sides and formed with an insertion opening through which anarticle is insertable into the respective bag, one of the sides only ofeach bag being formed with a suspension element detachable from therespective bag, the suspension elements being interconnected to retainthe bags in the stack and being formed with aligned suspension openingsproximal to the insertion openings.

[0017] The insertion opening can open into elongated pouches shaped toreceive a respective newspaper and each of the sides of each of the bagscan be formed with the respective pocket separate from the respectivepouch. The suspension elements themselves may be separate strips fusedto one of the bag walls in the area of the insertion openingsubstantially parallel to a perforation line between the respectivesuspension element and bag. The suspension strap or strip can be fusedto the inside or outside of the bag walls and each of the bags can beprovided with a drawstring or a rain protection flap with an adhesivestrip. The pocket may be attached to the end of the bag opposite theinsertion opening and can also have a unilaterally projecting flap alonga filling opening which is substantially parallel to the insertionopening and through which a computer disk or the like can be insertedinto the pocket. The flap can be made in one piece of the same materialas the pocket, preferably a transparent film or foil. The pocket flapcan be provided along an inner surface with an adhesive strip which can,if desired, be covered by a protective or masking strip.

BRIEF DESCRIPTION OF THE DRAWING

[0018] The above and other objects, features, and advantages will becomemore readily apparent from the following description, reference beingmade to the accompanying drawing in which:

[0019]FIG. 1 is a diagrammatic perspective view of a newspaper bagseparated from its stack for receiving a newspaper and a diskette;

[0020]FIGS. 2a-2 d are fragmentary perspective views of various variantsin the suspension area of the newspaper bag;

[0021]FIGS. 3 a perspective view of a stack composed of several bagsaccording to FIG. 1;

[0022]FIGS. 4a and 4 b are top views showing diagrammatically anapparatus for producing newspaper bags;

[0023]FIGS. 5a and 5 b are the side views corresponding to FIGS. 4a and4 b, respectively; and

[0024] FIGS. 6 to 10 are perspective views showing further modifiedembodiments of the bag.

SPECIFIC DESCRIPTION

[0025] The plastic foil bag 1 represented in FIG. 1 has at its upper endan insertion opening 2 for the bag, which extends all the way to a lowerbottom seam 3 of the bag and serves for instance for receiving anewspaper 4, a magazine or the like.

[0026] In the lower area of the bag 1 a pocket 5 is attached, also madeof plastic, for instance of transparent plastic material and is joinedby means of a fusion seam 6 with one of the bag walls of bag 1. Thispocket serves as an advertisements pouch and makes possible for instancethe insertion of a diskette 7, as indicated in FIG. 1. A closing flap 8,which can be an extension of the bag 1, as shown in FIG. 1, is providedfor closing the pocket 5. However the flap can also be an offset excessof the pocket material. In any case the flap is provided with anadhesive strip 9, so that it can be closed at the lower end after theinsertion of the diskette. When not in use, the adhesive strip 9 can becovered by a nonillustrated protection strip.

[0027] At the upper end, i.e. in the area of the insertion opening 2, inthe rear wall of the bag there is a perforation line 11. Basicallyparallel to this perforation line a suspension element in the form of aplastic strap or strip 13 is joined via a fusion seam. This strap 13 hasa suspension opening 14 as well as optional openings 15 for stackingpins and interlocking points 16. Via the latter several bags areincorporated in a stack, as indicated in FIG. 3.

[0028] In FIGS. 2a-2 d various suspension openings of the suspensionelements 13 are shown. The selected configuration corresponds to use andsuitability. It is possible to select the shape of the suspensionelements according to need and/or also to select the correspondingstrength of the material.

[0029]FIGS. 4a and 5 a show an unwinding station 18 for unwinding afirst web 19, a second web 21 for producing the bags, as well as anunwinding device 22 for web material 22 a not shown in detail forproducing the pocket 5. For producing the corresponding longitudinalfusion seams the webs are passed along a first longitudinal fusiondevice 23, as well as a second longitudinal fusion device 34. Furtherwith 25 an additional unwinder 25 for the strap strip is marked, whichis not shown in detail in FIGS. 4a and 5 a. A strip guide 26 is providedalong with an adhesive-strip unwinder 27 and a glue-applying station 28.Additionally underneath the adhesive strip unwinder there is also alongitudinal perforation device 29, and if required a grip-hole punchingdevice 31.

[0030] For the further production of the bags of the invention, themachine part shown in FIGS. 4b and 5 b is to be considered. Essentialfor the invention is a transverse fusion separating device 32, which hastwo fusion tools 33, 34 arranged substantially transversely with respectto the travel direction of the webs, which are synchronized in their upand down motion, the distance between them being twice the width of abag segment of the plastic foil web. In this way with each stroke orcycle two bags can be produced. A possible mechanized placement of thebags, or the pocket is feasible in practice, but is not shown here.

[0031] In support of the comparatively high cycling speed of at least100 to 125 cycles per minute, downstream of the transverse fusionseparator 32 a collection device 35 is arranged, which is subsequentlydescribed in greater detail. The collection device has first a transportdevice 36 which on one side extends up to a guide table 37, respectivelyguide belts in the area of the transverse fusion separator 32. Thetransport device 36 has endless holding belts 38 revolving about guiderollers. The holding belts can be provided with transport pins which canpenetrate the border area of the bags during bag advancement. The bagscan thus be transported to a pin-type stacking conveyor 39 which atleast partially lies underneath the transport device 36. By means of atake-down device not shown in detail the bags on the stacking pins 41can be knocked off and collected in stacks. Before the stacked bags aretaken off in packages, they are interlocked in packages by aninterlocking device not shown in the drawing.

[0032]FIGS. 6 and 7 show bags designed as so-called draw-string bags.Such a bag, after it has been torn off from the stack 17, can be closedat the insertion opening 2 by a drawstring 42.

[0033] A further alternative is shown in FIGS. 8 to 10. There the bag 1can be closed at its insertion opening 2 by a rain flap 43 provided withan adhesive strip 44.

We claim:
 1. A bag stack comprising a plurality of elongated plasticfoil bags each having a pair of opposite sides and formed with aninsertion opening through which an article is insertable into therespective bag, one of said sides only of each bag being formed with asuspension element detachable from the respective bag, said suspensionelements being interconnected to retain said bags in said stack andbeing formed with aligned suspension openings proximal to said insertionopenings.
 2. The bag stack defined in claim 1 wherein said insertionopenings open into elongated pouches shaped to receive a respectivenewspaper.
 3. The bag stack defined in claim 2 wherein one of said sidesof each of said bags is formed with a pocket separate from therespective pouch.
 4. The bag stack defined in claim 3 wherein each ofsaid suspension elements is a tear off segment separated from therespective one side of each bag by a perforation line.
 5. The bag stackdefined in claim 4 wherein the tear off segment is formed by a separatestrap fused with the respective one of said sides of the respective bagin an area of the respective insertion opening substantially parallel tothe perforation line.
 6. The bag stack defined in claim 5 wherein saidstrap is fused to an outside or inside of the respective bag and the bagis provided in said insertion opening with a draw string.
 7. The bagstack defined in claim 5 wherein said strap is fused to an outside orinside of the respective bag and each bag is provided with a rainprotection flap having an adhesive strip.
 8. The bag stack defined inclaim 5 wherein each pocket is attached to a respective bag at an end ofthe bag opposite the respective insertion opening and has a unilaterallyprojecting flap at a filling opening for the respective pocketsubstantially parallel to a respective insertion opening.
 9. The bagstack defined in claim 8 wherein said flap is formed in one piece of atransparent plastic foil with said pocket.
 10. The bag stack defined inclaim 8 wherein said flap is on the same side as the respective bag assaid suspension element.
 11. The bag stack defined in claim 8 whereinsaid flap is provided on an inside with an adhesive strip covered by amasking strip.
 12. A method of continuously producing plastic foil bagsinterconnectable to form a stack, comprising the steps of continuouslyfeeding first and second plastic foil webs; forming longitudinal andtransverse fusion seams in said webs to define respective bags andforming insertion openings for said bags; attaching a suspension elementin a region of the insertion opening of each of said bags by fusing acontinuously fed strip to one wall of each of the bags in the area ofthe respective insertion opening and fusing said strip thereto.
 13. Themethod defined in claim 12 wherein said strip is formed of a materialother than said foil.
 14. The method defined in claim 13, furthercomprising feeding a material capable of forming a pocket to a wall ofeach of said bags and fusing said material thereto while supplying saidmaterial with an offset to a bottom seam of the respective bag to form aflap for closing the respective pocket.
 15. An apparatus for thecontinuous production of stacks of interconnected plastic foil bags,said apparatus comprising an unwinding station for unwinding plasticfoil webs attached to be fused together to form such bags; alongitudinal fusion device and a transfer fusion device for fusing saidwebs together to form said bags whereby said bags for insertionopenings; means for feeding a strip to said bags and fusing said stripto one wall only of each of said suspension element detachable from therespective bags; and means for forming a perforation line in the area ofsaid insertion opening between each bag and a portion of said stripforming a respective strap whereby said straps are connectable toassemble a plurality of said bags in a respective stack.
 16. Theapparatus defined in claim 15, further comprising an adhesive stripunwinder for applying adhesive strips for feed bags and a protectionstrip unwinder for masking strips on adhesive strips.
 17. The apparatusdefined in claim 15 wherein said fusion devices include two fusionseparation tools disposed substantially transversely to a direction ofadvance of said webs and synchronized in respective up and down motions.18. The apparatus defined in claim 17, further comprising a collectiondevice downstream of said fusion separation tools in said direction andformed with pin-type stacking belts receiving the bags with pinsprojecting through said straps, the bags being held by said pins untilthey are knocked off by a takeoff device whereby said bags areinterlocked in the region of said straps.
 19. The apparatus defined inclaim 17, further comprising a downstream unwinder for applying adrawstring to each of said bags.